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1.
The title compound is prepared by solid state reaction of EuF3, EuF2+x, and Li2(CN2) at 700 °C and characterized by single crystal XRD, 151Eu Moessbauer spectroscopy, and magnetic measurements.  相似文献   

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Synthetic procedures were developed and X-ray diffraction analysis was performed for two mixed-ligand compounds of europium(III) with diethyldithiocarbamate ions and 2,2′-bipyridyl (2,2′-Bipy) or 1,10-phenanthroline (Phen): Eu(S2CN(C2H5)2)3(2,2′-Bipy) (I) and Eu(S2CN(C2H5)2)3Phen (II). The structures of the complexes consist of discrete monomer molecules; the coordination polyhedron of Eu (EuN2S6 is a node) is a distorted dodecahedron. Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 39, No. 2, pp. 300–309, March–April, 1997.  相似文献   

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Summary The crystal structure of (AsPh4)2[OsN(OH)(CN)4] has been determined from three-dimensional X-ray diffraction data. The [OsN(OH)(CN)4]2– ion has a distorted octahedral geometry with bond distances: ON = 1.606(5), Os-OH = 2.123(5) and Os-Cav = 2.068(8) Å. The osmium atom is displaced 0.26 Å from the equatorial cyano-carbon atom plane.  相似文献   

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The preparation of Se(CN) 4 was attempted by the reaction of SeF 4 with Me 3SiCN at low temperatures. However, selenium tetracyanide could not be detected by NMR spectroscopy; instead, the decomposition product Se(CN) 2 was isolated and its crystal structure was redetermined. In the structure of Se(CN) 2, layers are present with secondary Se...N interactions. The structure of Se(CN) 4 and its reductive decomposition reaction has been calculated at the MP2 level of theory.  相似文献   

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An anhydrous orthophosphate, K3Eu5(PO4)6 (tripotassium pentaeuropium hexaphosphate), has been prepared by a high‐temperature solid‐state reaction combined with hydrothermal synthesis, and its crystal structure was determined by single‐crystal X‐ray diffraction analysis (SC‐XRD). The results show that the compound crystallizes in the monoclinic space group C2/c and the structure features a three‐dimensional framework of [Eu5(PO4)6], with the tunnel filled by K+ ions. The IR spectrum, UV–Vis spectrum and luminescence properties of polycrystalline samples of K3Eu5(PO4)6, annealed at temperatures of 650, 700, 750, 800 and 850 °C, were investigated. Although with a full Eu3+ concentration (9.96 × 1021 ions cm?3), the self‐activated phosphor K3Eu5(PO4)6 shows s strong luminescence emission intensity with a quantum yield of 37%. Under near‐UV light excitation (393 nm), the series of samples shows the characteristic emissions of Eu3+ ions in the visible region from 575 to 715 nm. The sample sintered at 800 °C gives the strongest emission and its lifetime sintered at 800 °C (1.88 ms) is also the longest of all.  相似文献   

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Summary The crystal structure of the caesium salt of [OsO2(CN)4]2– has been determined from three-dimensional x-ray diffraction data. The orange crystals are monoclinic, space group C2/m with a=12.125(2), b=8.284(1), c=5.457(1) Å, =102.01(1)° with two molecules per unit cell. The final R value using 778 observed reflections and anisotropic thermal parameters for all atoms was 0.028. The [OsO2(CN)4]2– ion has an octahedral geometry. Bond distances: Os=O=1.750(8)Å and Os–C=2.093(9)Å.  相似文献   

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Synthesis of Y2O2(CN2) and Luminescence Properties of Y2O2(CN2):Eu Crystalline powders of the new compound Y2O2(CN2) were prepared by solid state reactions from different mixtures of YCl3/YOCl/Y2O3 and Li2(CN2) at temperatures between 620 °C and 650 °C. Structure refinements based on X‐ray powder diffraction revealed that trigonal Y2O2(CN2) crystallizes with a structure that is closely related to that of Y2O2S, whereas linear N‐C‐N units replace sulphur atoms in Y2O2S. In addition, a hexagonal polytype of Y2O2(CN2) was obtained in which a different stacking sequence of yttrium atoms creates a doubling of the c‐axis. Europium‐doped samples of Y2O2(CN2) were prepared and the luminescence properties of Y2O2(CN2):Eu are presented.  相似文献   

11.
The reaction of (C6F5)2HGeGeH(C6F5)2 with triethylbismuth affords a new polynuclear germylbismuth derivative, [(C6F5Ge]4Bi2 (1). The metal framework of molecule1 has the form of a gable roof built by two central Bi atoms and four peripheral Ge atoms with covalent Bi-Bi bonds [3.045(3) Å], Bi-Ge [2.724(5)-2.755(4) Å] and Ge-Ge [2.444(6), 2.465(6) Å].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 921–924, May, 1994.  相似文献   

12.
[catena‐Bis(1,2‐diaminoethane)nickel(II)‐µ‐dicyanoargentate]‐dicyanoargentate, [Ni(en)2Ag2(CN)4], was synthesized and its chain‐like crystal structure was determined by X‐ray crystal analysis. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

13.
S4(CN)2 crystallizes in the monoclinic space group P21/c with a = 885.7 pm, b = 794.2 pm, c = 1032.6 pm, β = 109.0° (at 173 K). The molecules occupy general sites but are of approximate C2 symmetry. The conformation of the molecules is all-trans with torsional angles CSSS = 74.6° and 81.7° and SSSS = 84.8°. The central SS bond (201.7 pm) is much shorter than the terminal SS bonds (av. 206.8 pm). There are no stronger than van-der-Waals type intermolecular interactions.  相似文献   

14.
(NH_4)_2WS_4,CuCl 和 NH_2OH·HCl 在吡啶溶液中反应可得到红色晶体 WCu_4S_4Cl_2(NC_5H_5)_6.晶体属于单斜晶系,空间群为为 C_(2h)~6-C2/c.晶胞参数为:a=14.883(9),b=12.580(6),c=20.318(9)(?);β=100.50(4)°;Z=4.结构用重原子法解出,经最小二乘法修正,偏离因子R=0.069.分子具有 C_2点群对称性,中心 W 原子以平面四方形形式和四个 Cu 原子结合.W—Cu间平均距离为2.673(?).该化合物为钨铜的混合金属原子簇化合物.  相似文献   

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The reaction of vanadium(III) acetylacetonate with HBF4 in acetonitrile yields [(CH3CN)5V-O-V(CH3CN)5][BF4]4, a material that serves as a convenient precursor to other [V-O-V]4+ species such as [(bipy)2(CH3CN)V-O-V(CH3CN)(bipy)2][BF4]4 (bipy=2,2'-bipyridine). Single-crystal X-ray diffraction shows that the V-O-V linkage of [(CH3CN)5V-O-V(CH3CN)5]4+ is linear. An Evans method measurement of the solution-phase magnetic susceptibility indicates strong ferromagnetic coupling between the vanadium centers. Magnetic susceptibility (chi) and magnetization (M(H)) data for a powdered sample and for a single crystal oriented with its V-O-V axis parallel to the applied field were measured over 1.8-300 K. The results suggest that the V(III) centers are ferromagnetically coupled with J approximately 72 K (approximately 50 cm(-1)) yielding a ground state with a total spin Stotal=2. Theoretical fit to the M(H) plot for the single crystal yielded g||=2.01+/-0.01 and the zero-field splitting parameter D=0.60+/-0.04 K (0.42+/-0.03 cm(-1)). EPR measurements at 34 and 101.6 GHz are consistent with the Stotal=2 ground state and yield g||=1.9825, g perpendicular=1.9725 and D=0.57+/-0.03 K.  相似文献   

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《Solid State Sciences》1999,1(4):233-243
Diamido-difluoro-tin Sn(ND2)2F2 can be produced by ammonolysis from (NH4)2SnF6 at 633 K. The compound is a product formed from Sn(ND3)2F4 during the ammonolysis reaction. Sn(ND2)2F2 isostructural with Sn(NH2)2F2 crystallizes in space group C2/m with lattice constants a = 1072.92(7), b = 325.97(1) pm, c = 505.79(4) pm and β = 105.713(6) ° (V = 170.28(1) ·106 pm3) containing two formula units per unit cell. Data refinement by the Rietveld method of neutron time-of-flight data collected at POLARIS yields a weighted profile R-value Rwp = 0.022. Tin is octahedrally coordinated by two fluorine atoms and four amido groups. The octahedra are connected to one-dimensional chains by edge sharing. The ND2 groups are in the bridging position whilst the fluorine atoms are terminal. Nearly linear (175.2(4) °) and angular (134.35(8) °) N-D···F hydrogen linkages connect the chains.  相似文献   

20.
New compounds, Sr2Ga(HPO4)(PO4)F2 and Sr2Fe2(HPO4)(PO4)2F2, have been prepared by hydrothermal synthesis (700°C, 180 MPa, 24 h) and characterized by single-crystal X-ray diffraction. Sr2Ga(HPO4)(PO4)F2 crystallizes in the monoclinic space group P21/n with a = 8.257(1) Å, b = 7.205(1) Å, c = 13.596(2) Å, β = 108.02(1)°, V = 769.2(2) Å3 and Z = 4 and Sr2Fe2(HPO4)(PO4)2F2 in the triclinic space group P21/n with a = 8.072(1) Å, b = 8.794(1) Å, c = 8.885(1) Å, α = 102.46(1)°, β = 115.95(1)°, γ = 89.95(1)°, V = 550.6(1) Å3 and Z = 2. Structures are both based on different sheets involving corner-linkage between octahedra and tetrahedra. The sheets are linked by Sr2+ cations. Structural relationships exist between the descloizite mineral and the title compounds.  相似文献   

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